Applications of Power Increasing Sequences
Hikmet Seyhan Ozarslan *
Department of Mathematics, Erciyes University, 38039 Kayseri, T¨urkiye.
*Author to whom correspondence should be addressed.
Abstract
This paper establishes a general theorem on absolute matrix summability for infinite series by employing the class of quasi-f-power increasing sequences in place of almost increasing sequences. The study is framed within the φ − |B, pn|k summability method associated with a positive normal matrix B = (bnv) and a sequence of positive coefficients (pn). After recalling the relevant Riesz mean, normal matrix transformations, and bounded variation assumptions, the paper states a theorem that extends Bor’s result on absolute Riesz summability factors. The theorem assumes standard monotonicity and boundedness conditions on the matrix entries, the sequence (λn), the auxiliary sequence (βn), and the n-th Ces`aro mean (tn) of (nan). Under these conditions, it is shown that the transformed series anλn is summable by the φ−|B, pn|k method for k ≥ 1. The proof proceeds through Abel’s transformation, decomposes the matrix transform into four terms, and establishes convergence estimates for each term by using H¨older’s inequality, the properties of the matrix, and the consequences of quasi-f-power increasing sequences. The result confirms that replacing almost increasing sequences with the broader quasi-f-power increasing framework preserves the required summability conclusion. Several special cases follow from the theorem, including results for quasi-δ-power increasing sequences, | ¯N , pn|k summability, and |B, pn|k summability under appropriate choices of parameters. Thus, the theorem provides a unified formulation for related absolute summability factor results within the stated hypotheses. No additional assumptions are introduced beyond those specified in the theorem, and the derived consequences are presented only as formal reductions of the main result. This maintains a close connection between the generalised theorem and the earlier summability factor results considered in the manuscript.
Keywords: Absolute matrix summability, almost increasing sequences, bounded variation, H¨older’s inequality, infinite series, normal matrices, quasi-δ-power increasing sequences, quasi-f-power increasing sequences, Riesz means, summability factors